Ok here is what I like to know,
many of you have been on bad situations recently during your cruise, sorry about your trip sonny, and now this open a few questions for any cruiser:
Here are few situations:

1. If for example they charter the ship and I am already on a few weeks before my cruise where penalties will be charge if I cancel,

what they do?
Do they refound my money or give me a credit??

In my case I can only travel on a certain time of the year and I have to ask for my week of vacation with months on advances, if for Reason they cancel the trip I will have to wait a year in order to even considering travel so a credit is not an option for me
Will they refound it without a credit??
Do we have anything to say on that matter??

2. If I something happen and the ship, for example broke engine on st. Thomas my first day of my cruise,

Do they will refound me my money or a future credit??
What happen if after that I don't want to cruise with the company anymore because the situation, they dont complete my cruise and its not my foult,
Will they give me my money back??

ok those situations are not the cruisers foult what we can do as our defenses on cases like that??

If a cruiseline has to cancel a sailing, you are entitled to a full refund even if in penalty. Sometime they will sweeten the offer if you take a future cruise instead for the inconvenience. They sometimes offer a half refund and a future cruise credit. However, if you want to be refunded in full, you are entitled to a full refund. This only applies if the cruise is cancelled.

A change in itinerary is a completely different situation. If you're on a ship and miss a port, the only thing you're entitled to is the port charge paid for that port. The cruiselines all reserve the right to changes, with or without your authorization. You accept this as part of the terms and conditions of every passage when you book. If you don't agree to their terms and conditions, you don't sail, with any line. Nothing but the refund of that one small port fee is obligated. In fact if they take you out to sea and never hit a single port on your itinerary because of mechanical problem or weather or any other reason, you are not entitled to a refund other than the port fees for ports missed. They do often up the compensation, like they did on Sonny's cruise. They want you back. It is not manditory that they provide such add'l perks or refunds.

Basically they hold all the cards once you set sail. Any complaining about compensation or missed ports is simply lost breath, time and energy. Take what they offer and go on and enjoy the balance of your cruise. The crew can't change the decision and neither can a passenger. We already know the result from a previous thread on what happens if you protest too much and become angry, obnoxious or try to organize other passengers to petition for more.

thanks forthe response
When I said the st. Thomas situation is because I embark on PR on sunday and st.Thomas is my first port of call like the carnival destiny route
so then
You will lose 6 days of your 7 day cruise after you already pay it??
Have this even happen
A ship that cannot continue, on the first port of call, what normally the cruise lines do on those cases??

You'd normally get 7 days on the ship, even if there were mechanical issues. You may just lose ports or time while they repair the ship. Then the ship will continue the sailing and hit as many ports as possible. That's exactly what happened to Sonny. He got the full number of days onboard, just missed some ports because of repairs in Barcelona. Nothing you can do but hope they make a generous offer like they did in that case. If you cruise, you take a chance. A chance that you'll see all the ports on your itinerary. Most of the time you do. In the rare circumstance that you miss ports, you are only entitled to port charges back. Anything else is up to the cruiseline.

I wouldn't get too wound up about the possiblity of a mechanical problem at the first port. RARELY does a ship encounter enough damage to cause it to be stuck in port. In fact, Sonny's cruise was the first one I have heard of and it was only stuck because the Spainish safety organization was holding them to the letter of the law and not letting them set sail with the stabilzer deployed. The ship would have still been able to sail. The only other situation I have heard of was izopod issues with one of the Carnival ships. The ship could not make its full speed, so the itinerary had to be changed to make the distance of travel less to make up for the slower speed. But the passengers still got a full cruise out of it. In fact that ship operated like that for months until it was time for its scheduled dry dock where they could fix the izpod.

So, mechanical problem DO happen. The ships are complex machines after all. So break downs do happen. BUT most of the time they can fix issues without affecting the cruises.

While in Portugal, we were first told about the ship's mechanical problem a 5:30 pm when we were suppose to be on our way to Cadiz, Spain. We ended up being anchored for 33 hours until the stabilizer was cut off. As a result, we missed both Cadiz, and Malaga, Spain. Our ship just sailed straight to Barcelona. There was some compensation to all passengers which was more than RCCL had to pay. We still had a great time, and I would do it all over again. By the way, the Navigator continue sailing out of Barcelona without further repair. A new stabilizer will be installed during dry dock.